Antibodies specific for TROP-2 and their uses

Abstract

The present invention provides antibodies that specifically bind to trophoblast cell-surface antigen-2 (Trop-2). The invention further provides antibody conjugates comprising such antibodies, antibody encoding nucleic acids, and methods of obtaining such antibodies. The invention further relates to therapeutic methods for use of these antibodies and Trop-2 antibody conjugates for the treatment of a condition associated with Trop-2 expression (e.g., cancer), such as colon, esophageal, gastric, head and neck, lung, ovarian, or pancreatic cancer.

It is claimed: 
     
       1. An isolated antibody, or an antigen binding fragment thereof, which specifically binds to Trop-2, wherein the antibody comprises
 (a) a heavy chain variable (VH) region comprising (i) a VH complementarity determining region one (CDR1) comprising the sequence SYWIN (SEQ ID NO: 40), GYTFTSY (SEQ ID NO: 41), or GYTFTSYWIN (SEQ ID NO: 42); (ii) a VH CDR2 comprising the sequence NIX 1 PSDSYSNYNX 2 KFKD wherein X 1  is Y or F; X 2  is Q or K (SEQ ID NO: 51), or X 1  PSDSY wherein X 1  is Y or F (SEQ ID NO: 52); and iii) a VH CDR3 comprising the sequence GSX 1 FDY wherein X 1  is S or G (SEQ ID NO: 53); and 
 (b) a light chain variable region (VL) region comprising (i) a VL CDR1 comprising the sequence RASQTIGTSIH (SEQ ID NO: 59); (ii) a VL CDR2 comprising the sequence YASESIS (SEQ ID NO: 60); and (iii) a VL CDR3 comprising the sequence X 1 QSX 2 SWPFT wherein X 1  is Q or S; X 2  is N or F (SEQ ID NO:64). 
 
     
     
       2. An isolated antibody, or an antigen binding fragment thereof, which specifically binds to Trop-2, wherein the antibody comprises:
 a VH region comprising a VH CDR1, VH CDR2, and VH CDR3 of the VH sequence shown in SEQ ID NO: 13; and 
 a VL region comprising VL CDR1, VL CDR2, and VL CDR3 of the VL sequence shown in SEQ ID NO: 12. 
 
     
     
       3. The antibody or the antigen binding fragment of  claim 2 , wherein the VH region comprises (i) a VH CDR1 comprising the sequence SYWIN (SEQ ID NO: 40), GYTFTSY (SEQ ID NO: 41), or GYTFTSYWIN (SEQ ID NO: 42); (ii) a VH CDR2 comprising the sequence NIFPSDSYSNYNKKFKD (SEQ ID NO: 46) or FPSDSY (SEQ ID NO: 47); and (iii) a VH CDR3 comprising the sequence GSGFDY (SEQ ID NO: 48). 
     
     
       4. The antibody or antigen binding fragment of  claim 3 , wherein the VL region comprises (i) a VL CDR1 comprising the sequence RASQTIGTSIH (SEQ ID NO: 59); (ii) a VL CDR2 comprising the sequence YASESIS (SEQ ID NO: 60); and (iii) a VL CDR3 comprising the sequence SQSFSWPFT (SEQ ID NO: 62). 
     
     
       5. The antibody or the antigen binding fragment of  claim 4 , wherein the VH region comprises the sequence shown in SEQ ID NO: 13 or a variant with one or several conservative amino acid substitutions in residues that are not within a CDR and/or the VL region comprises the amino acid sequence shown in SEQ ID NO: 12 or a variant thereof with one or several amino acid substitutions in amino acids that are not within a CDR. 
     
     
       6. The antibody or the antigen binding fragment of  claim 5 , wherein the antibody comprises a light chain comprising the sequence shown in SEQ ID NO: 68 and a heavy chain comprising the sequence shown in SEQ ID NO: 67. 
     
     
       7. A conjugate of the antibody or the antigen binding fragment of  claim 1 , wherein the antibody or the antigen binding fragment is conjugated to an agent, wherein the agent is selected from the group consisting of a cytotoxic agent, an immunomodulating agent, an imaging agent, a therapeutic protein, a biopolymer, and an oligonucleotide. 
     
     
       8. The conjugate of  claim 7 , wherein the agent is a cytotoxic agent. 
     
     
       9. The conjugate of  claim 8 , wherein the conjugate comprises the formula: antibody-(acyl donor glutamine-containing tag)-(linker)-(cytotoxic agent).